Now the only thing we do not know about the Siemens card is that if it
works better with simultaneous recording and playback, and simultaneous
recording of different channels (pids) on the same stream (frequency).
Hauppage crashes or creates garbled streams if you do not comment out
these features in dvbdevice.c.
I have Siemens DVB-C v1.5 (full featured) and it also adds artifacts and
sometimes crashes if transfer mode is enabled in VDR. Maybe the card isn't
fast enough for transfer mode because most of the artifacts come at scene
changes when bitrate is at maximum?